Ultrastructural study of granulomatous tissue in tonsillar malakoplakia

The ultrastructural study carried out in a case of tonsillar malakoplakia confirmed that granulomatous lesions consisted mainly of macrophages containing peculiar calcified inclusions (Michaelis-Gutmann bodies) considered pathognomonic for the disease. Moreover macrophages frequently contained ingested Gram-negative bacilli and presented aspects of mitochondrial degeneration and autophagy. These latter features were probably the consequence of bacterial infection rather than the expression of primary cellular defects, as the clinical evolution of this case of malakoplakia did not support the existence of generalized macrophage alterations.     

Activity Pattern of Echimyid Rodent Species from the Brazilian Caatinga in Captivity

The activity patterns of two closely related echimyid rodents (spiny rats) of the Brazilian Caatinga were studied. One species, Proechimys [Trinomys] yonenagae , is a fossorial dweller of fixed sand dunes. P. [T.] albispinus , inhabits remnants of the Atlantic rainforest areas. A third species, Trichomys apereoides , collected in granite formations in the Caatinga was also studied. The animals were kept individually in cages under controlled conditions and light-dark cycle of 12:12 h. Data were collect by Scan sampling every 2 h, over 3 days, and were analyzed by Cosinor method. All species were nocturnal. P. yonenagae showed a regular pattern of circadian activity and restricted its activity to subjective night. P. albispinus showed an intermittent pattern of activity, especially in the dark phase. T. apereoides showed a bimodal pattern with high crepuscular peaks of activity. A high level of synchrony was found in the activity among individual P. yonenagae . No sex differences were found in behavioral patterns of either P. yonenagae or P. albispinus . Since the two species of Proechimys share a common ancestor, the differences that were found stress the importance of external selection over circadian rhythmicity.     

Small animal irradiator dose distribution verification using radioluminescence imaging

The main objective of this work was the development of a novel 2D dosimetry approach for small animal external radiotherapy using radioluminescence imaging (RLI) with a commercial complementary metal oxide semiconductor detector. Measurements of RLI were performed on the small animal image‐guided platform SmART, RLI data were corrected for perspective distortion using Matlab. Four irradiation fields were tested and the planar 2D dose distributions and dose profiles were compared against dose calculations performed with a Monte Carlo based treatment planning system and gafchromic film. System linearity and RLI image noise against dose were also measured. The maximum difference between beam size measured with RLI and nominal beam size was less than 8% for all the tested beams. The image correction procedure was able to reduce perspective distortion. A novel RLI approach for quality assurance of a small animal irradiator was presented and tested. Results are in agreement with MC dose calculations and gafchromic film measurements.     

Radioimmunotherapy trials in germ testicular carcinoma: a phase I study

Two patients with germ cell testicular cancer were submitted to radioimmunotherapy (RIT) by using the monoclonal antibody 131I-radiolabelled (MoAb) H17E2, raised against placental alkaline phosphatase (PLAP). Both patients had been previously treated with repeated chemotherapy regimens assisted by autologous bone marrow transplant (ABMT), that, in the end were unsuccessful, thus necessitating further experimental treatment. RIT was well tolerated and the targeting of multiple neoplastic lesions was satisfactory. Nevertheless, the clinical results of treatment were minimal owing to the extension of the tumour. The data obtained suggest the possibility of applying this form of treatment in patients with minimal residual disease after previous traditional chemotherapy regimens.